BuddyPress requires that users activate their accounts after registering. The activation link is sent via email to the registrant. It is likely that either your php mail configuration is messed up or that the email in question went into the user’s spam folder.

It did help previous users that was in limbo but how can i prevent this problem from happening? Every time a user sigh up, they are asked for the activation code and the email thats sent out after they sign up has the activation code but its not reading it.